Diaphragm-horn.



M HUTCHISON.

DIAPHRAGM HORN.

APPLICATION FILED MAY H. 1911.

Patented Aug. 3, 1915.

2 SHEETSSHEET I.

i luvs/ml? WIZNESSES M. R. HUTCHISON.

DIAPHRAGM HORN.

APPLICATION FILED MAY H, I911.

1,148,687. vPatentedmg. 3,1915.

2 S'HEETSSHEET 2.

2 y 2 Z 2 AWE/V70]? warmmvgr @FFECE.

MILLER REESE HUTCHISON. OF NEST ORANGE, NEW JERSEY, ASSIGNGE TO LOVELL EICCONNELL MANUFACTURING COMPANY, A CORPGBATION OE DELAWARE.

DIAPHRAGM-HORN.

Application filed May 11, 1511.

Be it known that l. Miriam Rinssn lirUTCH- nsox, a citixen oi the United States, and resident of \Vest Orange, in the county of Es sex and State of New Jersey, have invented certain new and useful improvements in Diaphragnrl'lorns. of which the following a specification;

This inrention 'relaies to alarm or signa ing apparatus. will heusel ul for man dill'erent purgoses, laitespeciall for use on vehicles, heats. factories and elsewhere where a powerful sound is desirable.

In numerous prior applications and patents I hare disclosed various forms and modes of o] )eration or mochanicaliy-actuatial diaphragm horns adapted for such purposes, and have discussed various principles of construction applicable as well in the present case. As illustrative of the hroader principles of .such sigmls I, have hitherto shown a preferred form of diaphragm. whicl wholl clamped about its edges.

In accordance with my present ini'ention l generate the sound by means of a diaphragm unclamped and free for more or bodily moreuient t one or more of its edges, whereby increased amplitude of vibration is attained, and the llexure, where flexing occurs, ma}; he-transrersc, rather than. cirrular, and in such case the l'lexuro is preferably at right angles to the grain oi the metal, wood or other material of the diaphragm. With this diaphragm 1 preferably associate a horn or projector. which casts the sound in the desired direction. and may also act as an amplifier. 1 lind that by vibrating the diaphragm of such a horn signal at high frequency and through a considerable amplitude by power means acting on the diaphagni through mechanical connections, asound of large volume, imperative quality and great carrying power may he obtained.

For best results, the horn should he so proportioned that the inclosed air column has a virtual length of hall" a wave length at the normal operating frequency of the mechanisally-actuated, power-driven diaphragm. When this is the. case the air column and the diaphragm will rilirate in unison and the output of sound will he. maximum. Preferably, the prime irorer an electric n'iotor, and with such a rumor. or when other drire is employed permittiir, oi? a degree of Specification of Letters Patent.

its Yuri ems embodiments Serial No. 825,493.

slip, thesignal will be self-governing to hold the diaphragm to a rate of vibration synchronous with the horn or resonator, hecauae the power required of the motor to vihr ihe (,li ohragm at higher freipiency Will no :e; the tendencv of the diaphragm to vibrate out of iinison heing .j-ngly opposed by theair column esprciallywhen the resonator has a. considerable area the hase.

"r 3'. ine oiapniagiiexihle and I latter. in either erent. i mounted as to he supporte'l rharacteristically at one at one region, end, and freely dispiaceahle elsewhere. As so constituted. it n'iay he regarded as a f 'i;.l -1no\ahle tongue or reed. Preferably, the partlyweddinphragm is made of spring uniterial, especially sheet spring steel, but other material may he en'iployed. The diaphragm may be either pirotally supported or clamped or otherwise innnovahly held at one end i edge. In the. latter event it performs its rihratory to and fro increment hy fletiure. estahlishing a virtual pirot in the iicinity'ot its clamped portion. In certain instances it is desirable to provide a stationary abutment contacted by the diaphragm in its free movement in the direction away from the actuating means. or the diaphragm may strike against stops in hoth directions. Such an abutment, particularly whenemplo ed in connection with a piroted, more or less unyielding diaphragm or tongue, may cause the signal to operate with something of a clapper action. Such an abutment used in connection with a resilient diaphragm may cause the diaphragm to produce the alternate wares of compression and rarefaction partly by free mo ement and partly by central fiexure of the diaphragm held between opposed marginal supports. When the diaphragm is pirotally supported and resilient. and when the actuating means is so related thereto as to flex the diaph agm after coutactinguith the ahutment,'the abutment enahles the diaphra m to execute its .return movement hy virtue of the elastic staess un der which it has been placed. lVith a diaphragm clamped at one edge so that i is placed under elastic stress by the act of placement 'l'rom normal position. the a to'llexure past the stationlional stress due arr aluii mntrihul'es to the -rigor m clear of the same.

return movement. In other instances the return movements of the diaphragm or tongue may be largely or mainly under the influence of gravity.

Various mechanical connections may be employed for enabling the motor or other source of power to vibrate the partly-free diaphragm. I prefer to employ an act'u ator driven from a power shaft, the actuator being provided with one or more actuating projections, preferably cams, adapted to effect successive displacements of the diaphragm. \Yith suchthrust projections the diaphragm is forcibly displaced in one direction by the thrust and returns automatically under elastic stress or the action of gravity, or both, after the passage of the projection or tooth.' lV-ith such an actuator, the diaphragm may or may not be flung outward clear of the cam tooth, dependent onthe formation of the tooth, the speed of rotation, the nature of the 'dia 'phragm support, the range of free .move-' ment permitted, and the elasticity or rigidity of .the diaphragm or tongue. When the-"- abutinent is used, the diaphragm may contact therewith either While in the act of being forced by the cam or after being flung In the latter event, the resulting flexure past the abutment, or the more or less rigid impact thereagainst, as

' 1 of inc-losing case, taken at the joint between screws or bolts 13.

the sections thereof, the unclamped diaphragm and rotary actuator being shown in elevation; Fig. 3 is a front elevation, looking into the mouth of the horn; and Fig. 4: is a longitudinal section through the rear part of another form of signal, the parts in side being shown in elevation. 111.1 gs. 1 to 3, the diaphragm is shown at 10. It is incloscd in a' suitable case, an illustrative form of whiehis shown as compris ing the front section 11 and the rear section 12, which may be connected together by The front section 11 is provided with an opening 14 for the escape of sound. Preferably, the diaphragm or tongue is elongated and the openlng is elongated in the same direction. Obviously, however, the diaphragm may be of any desired outline,

l5 isa horn'jcoinmimicating atits base per action be.

with the opening 14, for projecting the sound in a forward direction. As already explained, best results are obtained by so proportioning the horn that it is resonant with the normal operating frequency of the tongue or diaphragm. I

The tongue may be of any suitable material, and it may be either stiff or flexible. 1n the latter instance, it is preferably of spring material, as sheet spring metal. it

is preferably supported or clamped at one end or edge, and freely displaceable at all other regions. In the form of the invention shown in Figs. 1 to 3, the diaphragm or tongue is pivot-ally supported on a pin or shaft 16. Preferably, it is received at its shaft end in a suitable clip or holder 17 journaled on or secured to the shaft.

buitablepower driving means are provided, an electric motor being preferably employed. The armature of such a motor is indicated at lb. Any suitable mechanical connections'may be interposed between the motor and diaphragm for vibratingthe lat ter. A simple and preferred embodiment is shown, the same including a disk 19, on the part. 111 the present instance, it is shown as formed with the holder 17. In operation, rotation'of the driver 19 successively displaces the diaphragm in one direction. In the particular construction illustrated, the return movements of the diaphragm are free, but it will be obvious that the diaphragm may be so coupled to the driver as to be forcibly displaced in both directions. The free return movement may be performed partly or largely under the influence of gravity. To this end the diaphragm or reed may be pivoted at its upper end, as

shown. The thicker and heavier the reed or tongue, the greater will be the effect of gravity in restoring it to normalposition. Preferably an abutment, such as the solid shoulder 23 adjacent the otherend of the diaphragm, is provided in position to'be contacted by the diaphragm Whenmoving under the impulse imparted by the driver.

Such an abutment causes-the tongue to operate with something of a clapper or hammer action, and the larger the abutment surface and the heavier and more nearly rigid the tongue, themore. pronounced will this clap-'* With a spring tongue or diaphragm, the abutment may alford a support to cooperate with thepivot or other fixedsupport, so that the "diaphragm is flexed between itstends, either b its own momentum or by thecontinued orcing by thecam after contact of the diaphragm j with the abutment. The energy so stored iii the'diaphragm enables it to spring back to 1 1 or past norma'l psition when the actuating projection has ridden off theanvii.

Best results are obtained Whenthe outline of the diaphragm or reed and the interior of-tlie case. closely conform toiea ch other, so that the diaphragm vibrates with. minimum clearance, and-therefore with,

minimum leakage around'its edges. The clearance shown in Fig. 2 might be reduced in practice. "The space between the diaphragm and the back yvall ofthe case may constitute a resonant space, or another horn may project from this side. n

F 15. 5 I illustrate a form of the invention showing that the diaphragm, here indicated by the character 10, may be fix- ;edlv instead-of pivotally supported. In this instance one en is shown'clamped between the forward and real-Ward sections '11 and 12* of a suitable case. The diaphragm is preferably of spring material. ,In the other illustrated form oi the invention, the actuating means engaged the tongue or the wear piece secured thereto, at. the opposite side of the support from the working area of the tongue.

' In the form shown in Fig. 4, the actuating impulses are applied to the body of the dia-. phragm. F01 this purpose, a suitable wear-- piece or anvil 22 may be riveted or otherwise secured to the Working portion of; the

diaphragm, in position to be engaged by the thrust projections on the driver 19'. In this instance, also, the diaphragm preferably Y its edges, a rotary actuator carrying an eccentric projection for engagement with said diaphragm are point spaced from the free hit vibrating end and arranged to cause repeat-,-

ed bodily-displacements of said diaphragm at high amplitude, velocity and rate, and

power means for driving said actuatorat a suflicient speed to cause said diaphragm to generate acoustic waves.

2. An alarm or signal, comprisinga case,

' a pivotally supported flexible sound-generating ,mcmber' therein, a horn communicatingwith the interior of the case, and mechanical means for vibrating said member the direction of the length of the horn and about its pivotal support comprising-.apower shaft and connections between said shaft and saidmember. I

' 3. An alarm or signaling device comprie ing, in combination, a horn, a vibratory tongue for generating the sound projected by the-horn, and mechanicahmeans for ac- I tuating the tongue comprising a powerdriven rotary member provided with care projections for displacingthe tongue and} causing rapid vibrations of a free end pore tion spaced from said cam projecticns.

9th 'dav of May, A. D. 1911.

MILLER REESE HUTCHISGN.

lVitnesses; 1

Iavrxc Nionneerrr, James 1). BROWN,

- Signed at New York city, in the county I of N-ew York, and State of New York, 

